Let's roll up our sleeves and solve this. We have 553 and we're going to multiply it by 51, essentially adding 553 to itself 51 times.
Step 1: 0 + 553 = 553
Step 2: 553 + 553 = 1106
Step 3: 1106 + 553 = 1659
Step 4: 1659 + 553 = 2212
Step 5: 2212 + 553 = 2765
Step 6: 2765 + 553 = 3318
Step 7: 3318 + 553 = 3871
Step 8: 3871 + 553 = 4424
Step 9: 4424 + 553 = 4977
Step 10: 4977 + 553 = 5530
Step 11: 5530 + 553 = 6083
Step 12: 6083 + 553 = 6636
Step 13: 6636 + 553 = 7189
Step 14: 7189 + 553 = 7742
Step 15: 7742 + 553 = 8295
Step 16: 8295 + 553 = 8848
Step 17: 8848 + 553 = 9401
Step 18: 9401 + 553 = 9954
Step 19: 9954 + 553 = 10507
Step 20: 10507 + 553 = 11060
Step 21: 11060 + 553 = 11613
Step 22: 11613 + 553 = 12166
Step 23: 12166 + 553 = 12719
Step 24: 12719 + 553 = 13272
Step 25: 13272 + 553 = 13825
Step 26: 13825 + 553 = 14378
Step 27: 14378 + 553 = 14931
Step 28: 14931 + 553 = 15484
Step 29: 15484 + 553 = 16037
Step 30: 16037 + 553 = 16590
Step 31: 16590 + 553 = 17143
Step 32: 17143 + 553 = 17696
Step 33: 17696 + 553 = 18249
Step 34: 18249 + 553 = 18802
Step 35: 18802 + 553 = 19355
Step 36: 19355 + 553 = 19908
Step 37: 19908 + 553 = 20461
Step 38: 20461 + 553 = 21014
Step 39: 21014 + 553 = 21567
Step 40: 21567 + 553 = 22120
Step 41: 22120 + 553 = 22673
Step 42: 22673 + 553 = 23226
Step 43: 23226 + 553 = 23779
Step 44: 23779 + 553 = 24332
Step 45: 24332 + 553 = 24885
Step 46: 24885 + 553 = 25438
Step 47: 25438 + 553 = 25991
Step 48: 25991 + 553 = 26544
Step 49: 26544 + 553 = 27097
Step 50: 27097 + 553 = 27650
Step 51: 27650 + 553 = 28203

So, 553*51 = 28203